Not too worried in fast water but in slow I'm in the sink the last foot or two camp, on occasions leave 3 or 4 inches away from fly un touched but on others add sinkant right up to about an inch from the eye. Sometimes I like this bit to be under but on occasions on certain flies, I like to see the last couple of inches in the air slightly from fly end then looping over and going straight under water (old fashioned I think?).
Acknowledge that others don't like this last approach, as sun can shine off air born part when it catches the light but evening times on well foliaged river I find that spot on. Has to be said when it's warm and slow / calm getting the tippet to break through the surface can be a pain and seeing the 'jet trail' in the water surface is just plain annoying ... if I was a fish I'd laugh at my crude attempts

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